RSI, Moving Averages, and Support/Resistance: Technical Indicators in Plain English

Fundamentals — earnings, margins, valuation — tell you whether a company is a good business. Technical analysis tells you something different: what the stock's own price history suggests about supply and demand for the shares right now. The same tools are used on indices such as the Nifty 50 and Bank Nifty. Here is what the core indicators actually mean.

RSI: is the stock overbought or oversold?

The Relative Strength Index (RSI) is a 0–100 score measuring how sharply a stock has moved recently, relative to its own recent price swings. Above 70 is generally read as overbought — the stock has risen fast enough that a pause or pullback becomes more likely. Below 30 is oversold — the reverse.

RSI is not a prediction. It is a measure of momentum extremes. A stock can stay overbought for a long stretch during a genuinely strong trend, so RSI is one input to weigh, not a standalone buy or sell signal.

Moving averages: where is the trend, smoothed out?

A moving average is simply the average closing price over a set window — most commonly 50 days (the shorter-term trend) and 200 days (the longer-term trend). Smoothing out day-to-day noise makes the underlying direction easier to read.

The relationship between the two carries its own meaning. The 50-day average crossing above the 200-day (a golden cross) is widely watched as a bullish trend-shift signal; the reverse (a death cross) as bearish. Neither guarantees anything — they are pattern-recognition heuristics with a long track record of imperfect signals, not laws of physics.

Support and resistance: where has the crowd acted before?

Support is a price level where a stock has repeatedly stopped falling and bounced back up — buyers have shown up there before. Resistance is the mirror image: a level where selling has repeatedly capped further gains.

These are not fixed lines a stock literally cannot cross. They are historical evidence of where the balance of buyers and sellers has shifted before, which sometimes — not always — repeats. Traders often turn the previous session's high, low and close into pivot levels for the same reason.

The honest limitation

Technical analysis reads price history, not the business behind the ticker. It cannot tell you whether a company's next results will beat or miss, or whether its balance sheet can survive a downturn. That is why technical signals work best alongside fundamentals, and why a written trading plan with a stop-loss matters more than any single indicator.

What technical analysis is trying to do

Fundamental analysis asks whether a business is good and what it is worth. Technical analysis asks a different question: what are buyers and sellers doing, and where might they act next? It works from the price and volume history of a stock or index, on the idea that those records reflect the collective behaviour of everyone trading it, including their hopes and fears.

Traders on NSE and BSE apply these tools to individual shares, to the Nifty 50 and Bank Nifty indices, and to futures and options. They are used to time entries and exits, to place stop-losses and to judge whether a trend is strengthening or tiring. They are aids to judgement, not crystal balls, and this article shows how each of the main ones is calculated so that you understand what it is really telling you.

How RSI is calculated

The Relative Strength Index compares recent gains with recent losses over a set period, most commonly 14 days:

Suppose over 14 days the average up-day gain is ₹1.20 and the average down-day loss is ₹0.80. RS is 1.5, so RSI = 100 − 100 ÷ 2.5 = 60. If gains and losses were equal, RS would be 1 and RSI 50. Readings above 70 are conventionally called overbought and below 30 oversold, but in a strong trend RSI can stay above 70 for weeks. Treat extreme readings as a prompt to look closer, not as a sell or buy order.

Moving averages: simple and exponential

A simple moving average (SMA) is the plain average of the last N closing prices. If the last five closes are ₹100, ₹102, ₹101, ₹103 and ₹104, the 5-day SMA is 510 ÷ 5 = ₹102. Tomorrow, the oldest price drops out and the newest is added, so the average moves with the price.

An exponential moving average (EMA) gives more weight to recent prices, so it reacts faster. Traders use short averages (such as 20 days) for quick trends, and the 50-day and 200-day averages for the medium and long-term trend.

Support, resistance and pivot points

Support is a price zone where buying has repeatedly halted a fall; resistance is a zone where selling has repeatedly capped a rise. They are zones rather than exact prices, and they tend to become weaker each time they are tested.

Many intraday traders on NSE derive levels for the coming day from the previous session's high (H), low (L) and close (C) using pivot points: pivot P = (H + L + C) ÷ 3; first resistance R1 = 2P − L; first support S1 = 2P − H. If the previous day's H, L and C were 105, 98 and 102, then P = 305 ÷ 3 = 101.67, R1 = 203.33 − 98 = 105.33 and S1 = 203.33 − 105 = 98.33. The maths is mechanical, so it does not predict; it gives a common reference many traders are watching.

Volume, time frames and confirmation

Where technical analysis goes wrong

Test yourself

Technical tools work best alongside the fundamentals. Continue with EPS, P/E and the bull, base and bear articles to judge what a stock is worth before you decide when to act.

On NSE and BSE: what to keep in mind

Frequently asked questions

What does an RSI above 70 mean?

It means the stock has risen sharply relative to its recent swings and is considered overbought — a pullback becomes more likely, but in a strong trend RSI can stay above 70 for a long time.

What is a golden cross?

A golden cross happens when the 50-day moving average crosses above the 200-day moving average. It is widely watched as a sign that the trend may be turning up, but it is not a guarantee.

Are support and resistance levels guaranteed to hold?

No. They show where buyers or sellers have acted before, and a level that has held many times can still break, so use them alongside a stop-loss.

Disclaimer: this article is for education only. References to NSE, BSE and Nifty are for context and are not recommendations. It is not investment advice, and investingg.in is not a SEBI-registered advisor.